(19)

(11)

EP 0 846 087 A1

(12)

(43) Date of publication: 10.06.1998 Bulletin 1998/24 (21) Application number: 96926411.0 (22) Date of filing: 14.08.1996

(51) International Patent Classification (IPC):  C03B 23/ 025( . ) (86) International application number: PCT/FI1996/000439 (87) International publication number: WO 1997/008109 (06.03.1997 Gazette 1997/11)

(84) Designated Contracting States: AT BE CH DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE (30) Priority: 25.08.1995 FI 19950003999 (71) Applicant: Tambest OY 33701 Tampere (FI)	(72) Inventor: LAMMI, Petri FIN-33710 Tampere (FI) (74) Representative: Kahilainen, Hannu Juhani  Tampereen Patenttitoimisto Oy, Hermiankatu 6 33720 Tampere 33720 Tampere (FI)